Thursday, September 20, 2012

When not to quote yourself

But I’ve long recognized the complexities in ice behavior that will
probably result in some ice persisting, even in summer, through that
span in some places and that also guarantee the path toward largely open
Arctic waters will not be smooth. This was evident to Arctic
researchers as far back as 2005, as I wrote in our “Big Melt” series at
that time:

Arctic researchers caution that there is something of a
paradox in Arctic trends: while the long-term fate of the region may be
mostly sealed, no one should presume that the recent sharp warming and
seasonal ice retreats that have caught the world’s attention will
continue smoothly into the future.

“The same Arctic feedbacks that are amplifying human-induced climate
changes are amplifying natural variability,” explained Asgeir Sorteberg,
a climate modeler at the Bjerknes Centre for Climate Research in
Bergen, Norway.

Indeed, experts say, there could easily be periods in the next few decades when the region cools and ice grows.

I'm sure that cautious prediction made all sorts of sense . . . in 2005. Besides Mr. Revkin's level-headed commentary, what else did we have going for us in 2005? Fifty percent more sea ice than we have today (by area). Two hundred and fifty percent more sea ice (by volume):

August 2005, 9.2; August 2012 3.6 -- what a difference seven years makes.

To look at it from another perspective: from 1979 to 2005 (26 years) the ice fell from 16.9 km^3 to 9.2 km^3, a decline of 46%. Andrew Revkin cautions us the road ahead may be long and winding. From 2005 to 2012, the volume of ice falls from 9.2 km^3 to 3.6 km^3: a fall, in less than one third the time of more than 60%.

The world has changed. Recycled judiciousness from half a decade ago is a bit past its sell-by date.